The present invention generally relates to voice actuated dialing apparatuses, and more particularly to a voice actuated dialing apparatus which recognizes a voice input and makes an automatic dialing to a registered destination telephone number which corresponds to the voice input.
In a conventional dialing apparatus of a telephone, there is a need to manually dial a telephone number of a destination subscriber when making a telephone call. Hence, a user must remember the telephone number of the destination subscriber or refer to a public or personal telephone directory, and there is a large burden on the user especially when the user frequently makes telephone calls to a large number of subscribers.
Accordingly, a voice actuated dialing apparatus (hereinafter simply referred to as a voice-dialing apparatus) was proposed in a Japanese Laid-Open patent application No. 61-144157. According to this proposed apparatus, the user registers in advance standard patterns for voice recognition and response and corresponding telephone numbers. When making a telephone call, the user speaks a standard pattern (key word) such as a name of the destination subscriber he wishes to call instead of manually dialing the telephone number of the destination subscriber. Then, the apparatus recognizes the standard pattern and automatically dials one of the registered telephone numbers corresponding to the recognized destination subscriber. As a result, there is no need for the user to remember telephone numbers and the user can make a telephone call without referring to the telephone directory.
However, when a large number of telephone numbers are registered, the user may forget the standard patterns for retrieving each of the registered telephone numbers. Furthermore, when the user's voice changes due to catching a cold or the like, there are cases where it becomes impossible to retrieve the desired telephone number because the apparatus cannot recognize the standard pattern from the changed voice. Hence, it is conceivable to successively output the registered standard patterns through speech synthesis and make the user designate the desired standard pattern when it is outputted so that the apparatus can automatically dial a telephone number corresponding to the desired standard pattern. But this conceivable method suffers a problem in that the designation of the desired standard pattern is both troublesome and time consuming. In other words, the user may miss the desired standard pattern when he is interrupted while listening to the successive output of the registered standard patterns, such as when someone talks to the user. In addition, the user may erroneously designate a standard pattern which is outputted prior to the desired standard pattern. In these cases, the user must again listen to the registered standard patterns from the beginning so that he may correctly designate the desired standard pattern.
On the other hand, the voice-dialing apparatus is generally provided with a search function so that the relationship of the registered standard patterns and telephone numbers may be outputted by speech synthesis and/or display. This search function is used when the user forgets the standard pattern for retrieving a telephone number and also when the user forgets whether or not a certain telephone number is already registered. But the search is made by successively outputting the registered standard patterns and telephone numbers by speech synthesis and/or display, and in a worst case, the search must be made to last registered standard pattern and telephone number before the desired standard pattern is found. As a result, there is a problem in that the search takes a long time to carry out. When a clustering is used for the search, it is possible to restrict a search range by entering a cluster number, but the user must remember which standard patterns belong to each of the clusters.
On the other hand, in the conventional voice-dialing apparatus, only one telephone number is registered with respect to one registered standard pattern. Hence, in the case where the destination subscriber has a plurality of telephone numbers but the line is busy when the telephone call is made responsive to the standard pattern corresponding to a first telephone number, the user must once hang up manually and call again later using the same standard pattern or make another call using another standard pattern corresponding to a second telephone number. Thus, when it is only possible to register one telephone number with respect to one registered standard pattern, it is both troublesome and time consuming for the user to find a line which is not busy, especially when the user wishes to use the telephone call on urgent matters and when one or more telephone numbers of the destination subscriber is in use for a long period of time.
But the voice-dialing apparatus can only make the automatic dialing when the destination telephone number is already registered. Thus, the user must register in advance the standard patterns for voice recognition and response and the corresponding telephone numbers. In other words, the user must manually dial a destination telephone number which is not registered, and when the user thereafter wishes to register this telephone number after finishing the call, the user must register the telephone number from the keys and also register the corresponding standard pattern by his voice. The user may register the telephone number and the corresponding standard pattern before calling that telephone number, but the user may be in a hurry and wish to make the call first. Therefore, when the user wishes to call the telephone number which is not registered and thereafter register that telephone number, there is a burden on the user in that the user must dial the same telephone number twice, that is, once to make the call manually and once to register the telephone number.
In addition, when registering the standard patterns for voice recognition and response and the corresponding telephone numbers, an area code of the telephone number for a first region is usually not registered when the voice-dialing apparatus is used in the first region. But when the voice-dialing apparatus is moved to a second region having an area code different from that of the first region, the voice-dialing can no longer be made to the destination subscriber in the first region because the area code of the first region which must be dialed before the destination telephone number is not registered together with the destination telephone number. Similarly, when the voice-dialing apparatus is moved to the second region and the voice-dialing is to be made to the destination subscriber in the second region, the call cannot be made because the area code of the second region which does not need to be dialed when in the second region is registered together with the destination telephone number because the voice-dialing apparatus was originally used in the first region. Therefore, when moving the voice-dialing apparatus from the first region to the second region with the different area code, the user must re-register all of the telephone numbers in the first and second regions so as to add or delete the area codes where necessary.
There are answering phones which record on a magnetic tape or the like a message from a caller when the user is out, and play back the message at an arbitrary time. On the other hand, the voice recognition rate of the voice-dialing apparatus is not 100%, and it is necessary to output the result of the voice recognition by a speech synthesis, for example, so that the user can confirm the destination subscriber before the call is actually made. Recently, there are answering phones provided with a speech synthesis apparatus which records and plays back the message in a form of a digitally encoded audio signal which is unaffected by a deterioration and the like of the magnetic tape. Thus, when applying the voice-dialing apparatus to such an answering phone, it is conceivable to use a speech synthesis apparatus in common for the confirmation of the result of the voice recognition and for the play back of the recorded message.
However, when a part for storing the standard patterns and a part for storing the telephone numbers are provided inside the telephone set, the voice-dialing can only be made from the telephone set to which the standard patterns and the telephone numbers have been registered. In addition, when a part for recording the message is provided inside the answering phone, a total time for recording the messages becomes fixed and it is difficult to cope with the user's needs. In addition, a hardware is required exclusively for setting the telephone set to an answering mode. Furthermore, it is difficult to maintain the telephone set compact when the part for storage is provided inside the telephone set.
Moreover, when the voice-dialing apparatus is applied to the answering phone provided with the speech synthesis apparatus, it is a waste that one speech synthesis apparatus must be provided for the speech recognition and another speech synthesis apparatus must be provided for the answering phone. Further, the answering phone must be manually set to the answering mode by the user when the user goes out, and the functions of the answering phone are not carried out when the user forgets to set the answering phone to the answering mode.
As described before, the line may be busy when the dialing is made. In this case, it is possible to make the voice-dialing later when the destination telephone number is already registered. But it is necessary to manually dial the same telephone number again when this telephone number is not registered. There are ordinary telephones provided with a re-dialing function, wherein a re-dialing is made to a last dialed telephone number responsive to a manipulation of a re-dial button. However, there are problems in that the telephone set must be provided with the re-dial button exclusively for instructing the re-dial operation and the user must still push the re-dial button in order to make the call. In addition, when the user forgets the last dialed telephone number, the user may erroneously re-dial to a wrong telephone number because there is no means for the user to confirm the last dialed telephone number.
Furthermore, as described before, the voice recognition rate of the voice-dialing apparatus is not 100%, and it is necessary to output the result of the voice recognition by a speech synthesis, for example, so that the user can confirm the destination subscriber before the call is actually made. The user may confirm the result of the voice recognition by voice or by pushing a confirm button, for example. Therefore, there is considerable burden on the user in that the user must confirm the destination subscriber with every call made by the voice-dialing.
Next, a description will be given on an example of a conventional voice-dialing apparatus by referring to FIG. 1 so as to explain some of the problems referred above. The voice-dialing apparatus generally has a handset 11, a voice recognition part 12 coupled to the handset 11, and an automatic dialing part 13 for controlling a coupling between the handset 11 and a subscriber line 14. When the user enters by voice a name or a word corresponding to a standard pattern (that is, a key word) of a destination subscriber through the handset 11, the voice recognition part 12 recognizes the standard pattern and selects one of registered telephone numbers corresponding to the recognized standard pattern. The automatic dialing part 13 makes the automatic dialing to the registered telephone number selected by the voice recognition part 12.
In this conventional voice-dialing apparatus, a number of telephone numbers which may be registered is limited. When the telephone numbers are already registered to the full capacity and some new telephone numbers need to be registered, it is necessary to delete a number of registered telephone numbers corresponding to the number of new telephone numbers to be registered. In this case, it is useful to utilize the search function so as to check all of the registered telephone numbers and select those telephone numbers which are unlikely to be used frequently in the future. However, contrary to the user's impression, some of the selected telephone numbers may actually be used frequently, and thus the user may erroneously delete the telephone numbers which are frequently used.
In addition, it is impossible to set the voice recognition rate to 100%. In addition, the user's voice may change with time, and for this reason, the recognition rate tends to gradually deteriorate with time. Accordingly, in actual practice, the voice data which is already registered is renewed or re-registered in order to cope with such deterioration in the voice recognition rate.
However, it is impossible for the user to determine which registered standard pattern has a poor recognition rate. Therefore, there is a problem in that it is extremely difficult for the user to accurately renew or re-register the voice data which actually needs to be renewed or re-registered.
On the other hand, when registering the destination subscribers, the user first enters the telephone number of the destination subscriber from the keys and then enters the standard pattern for identifying the destination subscriber by voice. The entries by the keys and voice may be made in conformance with a guidance (voice or display) provided by the voice-dialing apparatus. But when a large number of destination subscribers are registered at one time, it takes a considerable time to complete the registration. On the other hand, when the registration is carried out in small numbers, it is difficult for the user to keep track of which destination subscribers have been registered and which destination subscribers need to be registered.